Crayons are known which comprise a pigment component, an organic solvent, a resin component, a gelling agent and the like. Specific examples of such crayons are those prepared by gelling raw materials, i.e. at least one of dibenzylidene sorbitol, derivatives thereof, tribenzylidene sorbitol and derivatives thereof and a resin component (Japanese Examined Patent Publication No. 23619/1979). These crayons have the features that they remain unchanged in properties at elevated temperatures, and stick well to the surface of various materials to which a crayon is applied (such as metals, plastics and so on), and that the crayon layer on the material becomes so hardened as to inhibit the transfer of color to other materials.
Also known are crayons further improved in hardness, adhesion to the surface of a material, writability and other properties (Japanese Examined Patent Publication No. 41716/1980). These crayons comprise (a) at least one species selected from cellulose resins and vinyl resins, (b) at least one species selected from ketone resins, xylene resins, amide resins and terpene resins, (c) at least one species selected from dibenzylidene sorbitol, tribenzylidene sorbitol and derivatives thereof, (d) at least one species selected from glycols, ethers of glycols, esters of glycols and esters of benzoic acid, and (e) a pigment component.
However, even these crayons need to be further improved in writability (or ease of writing) for application to a wide variety of materials.
Moreover, in recent years, various countries have raised safety criteria for crayons. Thus it is now desired to develop crayons which assure meeting such high safety criteria. Especially there is room for further improvement of organic solvents to be used in crayons. For example, an alcohol (especially ethanol) may be used as the solvent only if the increase of safety is intended. However, the use of alcohol as the solvent fails to impart satisfactory writability and adhesion.